You Eat About a Credit Card of Plastic Every Week

Five Grams a Week. Every Week.

Let that number settle in for a moment. Five grams does not sound like much until you realize it adds up to about 250 grams per year -- over half a pound of plastic entering your body annually. Over a lifetime, that is roughly 44 pounds of plastic consumed by an average person.

The 2019 University of Newcastle analysis, which reviewed 52 existing studies on microplastic ingestion, estimated that humans consume approximately 2,000 tiny pieces of plastic per week. These particles come from an astonishing variety of sources, many of which you interact with daily without a second thought.

And here is the uncomfortable truth: there is currently no way to avoid microplastics entirely. They have infiltrated virtually every food chain, water source, and breathable air column on the planet.

Where Is All This Plastic Coming From?

Microplastics are defined as plastic fragments smaller than 5 millimeters. They come in two forms: primary microplastics, which are manufactured small (like the microbeads once used in exfoliating face wash), and secondary microplastics, which result from larger plastic items breaking down over time.

Here are the main routes into your body:

Drinking Water

This is the single largest source. A 2018 study by Orb Media tested tap water samples from more than a dozen countries and found microplastic contamination in 83 percent of samples worldwide. The United States had the highest contamination rate at 94 percent.

Bottled water is not better -- it is often worse. A 2018 study published in Frontiers in Chemistry tested 259 bottles from 11 brands across 9 countries. Ninety-three percent contained microplastic particles. The average was 325 particles per liter, with some bottles containing over 10,000 particles per liter. Much of this likely comes from the plastic packaging itself and the bottling process.

Food

Seafood is a major vector, particularly shellfish. Because we eat the entire organism -- including the digestive system where plastics accumulate -- a serving of mussels can contain 90 or more microplastic particles. But it is not just seafood. Microplastics have been detected in:

• Table salt -- A 2018 study in Environmental Science & Technology found microplastics in 90 percent of commercial salt brands tested worldwide. Sea salt had the highest concentrations.
• Beer -- German researchers found microplastic fibers in all 24 beer brands they tested.
• Honey -- Detected in multiple studies, likely from airborne contamination during production.
• Fruits and vegetables -- Plants can absorb nanoplastics through their root systems. A 2020 study found microplastics in apples, carrots, pears, and lettuce purchased from regular supermarkets.

Air

You are breathing plastic right now. Indoor air contains significantly more microplastic fibers than outdoor air, largely from synthetic textiles (polyester clothing, carpets, upholstery) that shed fibers constantly. A 2016 study estimated that a person inhales between 26 and 130 airborne microplastic particles per day.

These inhaled particles can deposit in lung tissue. A 2022 study published in Science of the Total Environment detected microplastics in human lung tissue samples for the first time, finding polypropylene and PET fibers in 11 of 13 samples.

What Happens to Plastic Inside Your Body?

This is where the science gets both fascinating and concerning, because we are still in the early stages of understanding.

The larger microplastic particles -- those bigger than about 150 micrometers -- likely pass through your digestive system without being absorbed. They enter, they travel, they exit. A 2018 pilot study confirmed the presence of microplastics in human stool samples from all eight participants across multiple countries.

But the smaller particles, particularly nanoplastics (under 1 micrometer), are a different story. These are small enough to potentially cross cellular barriers, enter the bloodstream, and accumulate in organs. In March 2022, researchers from the Vrije Universiteit Amsterdam published the first study detecting microplastics in human blood, finding PET, polystyrene, and polyethylene in 17 of 22 volunteers.

Animal studies have shown several potential mechanisms of harm:

• Inflammation -- Microplastics can trigger inflammatory responses in gut tissue, potentially contributing to conditions like inflammatory bowel disease.
• Endocrine disruption -- Many plastics contain or absorb chemicals like BPA and phthalates that mimic hormones. These can leach from plastic particles inside the body.
• Gut microbiome changes -- Mouse studies have shown that microplastic exposure can alter the composition of gut bacteria, with downstream effects on metabolism and immune function.
• Oxidative stress -- Nanoplastics have been shown to generate reactive oxygen species in cell studies, which can damage DNA and cellular structures.

What Can You Actually Do About It?

Complete avoidance is impossible in the modern world. But you can reduce your exposure significantly.

Water: Use a reverse osmosis or activated carbon water filter. These remove a substantial proportion of microplastics from tap water. Avoid bottled water when possible -- and never drink from a plastic bottle that has been sitting in a hot car, as heat dramatically increases plastic leaching.

Food: Reduce consumption of processed foods packaged in plastic. Do not microwave food in plastic containers -- heat accelerates the release of micro and nanoplastics. A 2023 study from the University of Nebraska found that microwaving plastic baby food containers released over 4 billion nanoplastic particles per square centimeter.

Air: Use a HEPA air purifier indoors. Vacuum regularly with a HEPA-filtered vacuum. Opt for natural fiber clothing and textiles where practical -- a single load of polyester laundry can release over 700,000 microplastic fibers into wash water.

General: Cut down on single-use plastics in your daily life. Use glass or stainless steel food storage containers. Choose loose-leaf tea over tea bags -- many tea bags are made with plastic mesh that releases billions of nanoplastics when steeped in hot water.

These steps will not eliminate your exposure, but they can meaningfully reduce it. Given that the average person's body is already dealing with significant biological processes just to maintain itself, reducing unnecessary stressors makes sense.

The Scale of the Problem

Plastic production has increased from 2 million tons per year in 1950 to over 450 million tons per year today. Only about 9 percent of all plastic ever produced has been recycled. The rest is in landfills, the environment, or -- increasingly -- inside living organisms.

Microplastics have been found on the summit of Mount Everest, at the bottom of the Mariana Trench, in Arctic sea ice, in Antarctic snow, in rainwater, and in the placentas of unborn babies. A 2020 study estimated that there are 14 million tons of microplastic on the ocean floor alone.

This is not a problem that individual consumer choices can solve, though those choices still matter. It requires systemic changes in how we produce, use, and dispose of plastic materials. In the meantime, we are all part of an unplanned, planet-wide experiment in chronic low-level plastic consumption.

The credit card you are eating this week is just the latest installment.

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